The Value Of (18)~F-FDG PET-CT In The Diagnosis And Prognosis Of The Patients With Malignant Effusions

Objective:(1) To evaluate the value of F-FDG PET-CT in the diagnosisof patients with effusions.(2) To investigate the valueof the SUVmax of serous cavity effusions and other clinical factors in the prognosis of patients with malignant effusions.Materials and methods:(1) A retrospective analysis were conducted in265patients with serous cavity effusions, which from March2011to February2013in Tianjin Medical University Cancer Institute and Hospital. And their PET-CT imaging data would be compared with pathology and clinical follow-up reports. All of the patients had no history of malignancy. SPSS21.0statistical Package was used in this study and P<0.05was considered as statistically significant. The causes and PET-CT diagnosis efficiency of different effusions was analyzed. SUVmax between benign or malignancy, and different age and gender in each effusion group was compared using independent-sample t-test.(2)214patients with serous cavity effusion caused by malignant tumor were diagnosed by PET-CT at Tianjin Medical University Cancer Hospital from March2011to February2014.And after the diagnosis a complete clinical follow-up materials were collected. Patients’survival were compared between different effusion. And survival time in different SUVmax, age, gender, metastasis of bony and other organs or not, CEA levels of all cases were compared using the Kaplan-Meier survival analysis and Log-rank test in the univariate analysis and in the multivariate analysis with the Cox proportional hazard regression model.Results:(1) Of265patients,247cases were proved to be malignant. PET-CT detected the original lesions in207cases. The total detection rate was83.81%. In113patients with pleural effusion,100case of malignancy were diagnosed by PET-CT,and it also diagnosed3benign lesions. There were6cases of false positive and4cases of false negative.Of the104patients with malignant tumor,89cases of primary tumors were detected by PET-CT with a detection rate of85.58%. And the sensitivity, specificity and accuracy were96.15%(100/104)、44.44%(4/9)、92.04%(104/113).39cases of malignancy and1benign disease were correctly confirmed by PET-CT for43patients with ascites. The diagnosis with PET-CT was wrong in3patients, which false positive in2and false negative in1case. The detection rate of PET-CT was87.50%(35/40). The sensitivity, specificity and accuracy were97.50%(39/40),33.33%(1/3),93.02%(40/43). In group of pericardial, effusion PET-CT correctly diagnosed30cases with malignant tumor and1case with nontumorous from35patients. Among these malignancy, PET-CT discovered primary tumors in26cases. The detection rate was81.25%. The sensitivity, specificity and accuracy were93.75%(30/32)、33.33%(1/3)、88.57%(31/35).In74cases of patients with polyserositis, there were67cases with cancer,1cases with benign lesions,2cases with false positive,4cases with false negative diagnosed by the PET-CT. Among them, primary tumors were found out in57cases with PET-CT.The detection rate was80.28%. The sensitivity, specificity and accuracy were94.37%(67/71)、33.33%(1/3).91.89%(68/74).Patients in each group were divided into2groups:benign or malignancy. And the SUVmax of effusion were calculated. The difference of SUVmax between malignancy and benign in pleural effusion was statistically significant (1.32+/-0.44vs0.98+/-0.32, P<0.05). While difference between SUVmax of malignancy and benign in ascites, pericardial effusion and polyserositis were not statistically obvious (P>0.05).71cases of pleural metastases,45cases of peritoneal anomalies, which included6cases of primary peritoneal carcinoma,20cases of pericardium metastases were detected. PET-CT also identified35cases of simple lymph node metastases,138cases of bones and other organs metastases.(2) Univariate analysis showed that the difference in survival time between different parts of the effusions was statistically significant (P<0.05). According to average SUVmax(1.3), all patients were divided into group A (SUVmax≤1.3) and group B (SUVmax>1.3).The median survival time in group A (11months) was significantly longer than that in group B (8months). Cox multivariate analysis showed that age, bony or other organs metastasis were considered as independent factors for predicting the prognosis of the patients (P<0.05). while gender, SUVmax of effusion, CEA levels were not (P>0.05).Conclusions:(1)Tumor metastasisis the common cause ofmalignant effusion. Pleural effusion and pericardial effusion are majorly caused by lung cancer. Peritoneal effusion is usually induced by the gastrointestinal tumors. According to the patients with polyserositis,the pathogenesis is complicated, while lung cancer cover the most population.(2)80%of primary cancer with effusion could be detected by PET-CT. PET-CT is valuable in detecting the primary focus of the tumor, especially in patients with effusions.(3)PET-CT is valuable not only in detecting the primary focus, but also in identificating the metastatic lesions, including bony and soft tissue metastases in a single examination. PET-CT is helpful in the selection of appropriate management for these patients.(4)The SUVmax in malignant pleural effusion is found to be higher in comparision with benign cases.While SUVmax of effusions in other parts show no significant difference between benign and malignant.(5)Difference between SUVmax of different age and gender show no statistically significance.(6)The survival time differs between different parts of the effusions. Polyserositis group has the shortest median survival time. Age, bony or other organs metastasis could act as independent predictive factors for the survived of the patients with effusion.